xcex1-Olefins are manufactured by oligomerizing ethylene using a transition metal containing catalyst, the xcex1-olefins are converted to trialkylaluminum compounds by contacting them with aluminum and hydrogen with heat and pressure. The trialkylaluminum compounds which are formed may be reacted with oxygen to form the corresponding trialkoxyaluminum compounds, which can be hydrolyzed to form xcex1-alcohols.
Higher trialkylaluminum compounds (HTAC), R313Al (I), in which the alkyl groups contain more than 4 carbon atoms, are useful particularly as chemical intermediates for the synthesis of xcex1-alcohols of the formula R32R33CHCH2OH (II) wherein R32 is hydrogen or alkyl and R33 is alkyl. xcex1-Alcohols containing 10 to 20 carbon atoms are useful as intermediates for the synthesis of detergents and other surfactants. Therefore improved methods of making (I) and/or (II) are commercial interest.
Generally speaking, linear xcex1-alcohols are often made utilizing the following steps, see for Instance B. Elvers, et al., Ed., Ullmann""s Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A28, 1996, p. 505-508 and references therein, and J. I. Kroschwitz, et al., Ed, Encyclopedia of Chemical Technology, 4th Ed., Vol. 1, John Wiley and Sons, New York, p. 894-903 and references therein, both of which are hereby included by reference.
(a) Triethylaluminum is produced by contacting under relatively high pressure and temperature a mixture of aluminum, hydrogen, ethylene and triethylaluminum (TEA). xe2x80x9cNewxe2x80x9d TEA is produced in the reactor. The liquid product is removed from the reactor, filtered and some is recycled back to the TEA reactor and some is used in the next step.
(b) The TEA used in the next step is now mixed with more ethylene under high pressure and with heating. The ethylene adds sequentially (oligomerizes) to each of the original ethyl groups in the TEA, forming HTACs.
(c) The product of the previous step is mixed with oxygen (a highly exothermic reaction) to form the corresponding trialkoxyaluminum compounds.
(d) The trialkoxyaluminum compounds are hydrolyzed to form an alpha-alcohol mixture and alumina. This process is effective but requires the use of high temperatures and pressures in two steps, and in these two steps pyrophoric alkylaluminum compounds are present, and so these steps must be done very carefully to protect the plant and workers safety. This adds to the cost of the overall process. Processes which would minimize such steps, and/or require less capital investment, and/or have lower operating costs, would therefore be favored.
U.S. Pat. Nos. 2,787,626, 3,032,574, 3,207,770 and 3,960,912 describe the synthesis of trialkylaluminum compounds from olefins, hydrogen, aluminum, and sometimes other ingredients. The use of olefins made with transition metal containing ethylene oligomerization catalysts is not mentioned.
U.S. Pat. Nos. 6,103,946, 4,689,437, 3,644,564 and 5,382,738, which are all hereby included by reference, describe the use of various transition metal containing catalysts to make olefins or mixtures of olefins by oligomerizing ethylene. No mention is made of making trialkylaluminum compounds or xcex1-alcohols from those trialkylaluminum compounds.
B. Elvers, et al., Ed., Ullmann""s Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A28, VCH Verlagsgesellschaft mbH, Weinheim, 1996, p. 505-508 and references therein, and U.S. Pat. No. 5,278,330 describe the overall commercial synthesis processes for making xcex1-alcohols, including the synthesis processes for making HTACs.
This invention concerns, a process for the manufacture of higher trialkylaluminum compounds, comprising, forming an xcex1-olefin or mixture of xcex1-olefins by oligomerization of ethylene using a transition metal containing oligomerization catalyst system, then contacting said xcex1-olefin or said mixture of xcex1-olefins with aluminum metal, hydrogen and a trialkylaluminum compound at a sufficient temperature and pressure, for a sufficient amount of time, to form a higher trialkylaluminum compound.
This invention also concerns a process for the manufacture of xcex1-alcohols, comprising:
(1) forming an xcex1-olefin or mixture of xcex1-olefins by oligomerization of ethylene using a transition metal containing oligomerization catalyst system;
(2) then contacting said xcex1-olefin or said mixture of xcex1-olefins with aluminum metal, hydrogen and a trialkylaluminum compound at a sufficient temperature and pressure, for a sufficient amount of time, to form a higher trialkylaluminum compound or a mixture thereof;
(3) contacting said higher trialkylaluminum compound or a mixture thereof with oxygen or other suitable oxidizing agent to form a higher trialkoxyaluminum compound or a mixture thereof; and
(4) hydrolyzing said higher trialkoxyaluminum compound or a mixture thereof to form an xcex1-alcohol or a mixture thereof.